Same problem. Says GameClient.exe is not responding. I looked for a way to run a repair on it, but couldn't find one (like WoW has haha). Was able to play last night, patched today (300-something MB), and now won't load past the Neverwinter page.
Voted "Love it!" Seems like, besides bugs which will be worked out in time, the difficulty is the main complaint. I don't play games because they're easy and I can win easily. I prefer a challenge.